NUI Galway scientists develop rapid test for potentially paralysing infection
Monday, 12 February 2001
When people complain of suffering from a tummy bug, it might be just a mild infection, which is easily treated leaving no after effects. Alternatively, they could be among the increasing number of sufferers in this country, who have contracted a form of gastroenteritis, which may lead to paralysis. Scientists at NUI, Galway have developed a rapid test to detect strains of Campylobacter jejuni (C. jejuni), the commonest cause of gastroenteritis worldwide, with the potential to cause a rare neurological complication, known as Guillain-Barré Syndrome (GBS).
"There are increasing concerns at the level of illness caused by C. jejuni infection, which now exceeds the combined total of enteritis cases caused by Salmonella, E. coli, and Shigella", says Dr. Anthony Moran of NUI, Galway s Department of Microbiology, who has done extensive research in this area. "Although numbers of sufferers in this country are on the increase, there is limited public awareness of the condition, which if not diagnosed and treated correctly, can have catastrophic consequences for the patient".
In total, 2085 cases of laboratory-confirmed C. jejuni enteritis were reported in 1999 in Ireland. In the UK and US, where there is significant public awareness of the condition, C. jejuni is regarded as a major contributor to employee absenteeism. It is estimated that 2 million working days per year are lost in the UK due to gastroenteritis caused by C. jejuni. Furthermore, there is an estimated annual incidence of C. jejuni-associated enteritis of between 2-10 million cases in the USA alone, and the condition costs in the region of $1.3-6.2 billion US dollars per annum.
Symptoms of C. jejuni infection usually include diarrhoea, fever, nausea, vomiting and abdominal cramps, which are often severe enough to mimic appendicitis. Enteritis most often results from consumption of untreated milk or water, or via consumption of undercooked poultry meat. Patients with C. jejuni enteritis usually recover within a few days but in a small proportion of cases, a rare neurological disorder, known as Guillain-Barré syndrome (GBS) develops 7-10 days after the onset of enteritis symptoms. According to Dr. Martina Prendergast, a member of Dr. Moran s research team, "the disease affects about 1-2/100,000 of the population per year, translating into 40-50 potential new Irish GBS cases each year". Significantly, Dr. Moran says that, "GBS has replaced polio as the leading cause of infectious paralytic disease. Moreover, he adds that, "when added to the cost of C. jejuni enteritis, treatment costs for GBS add up to a further $2 billion US dollars to the economic impact of C. jejuni infection in the USA each year".
Although it affects both sexes of any age, GBS affects men more commonly than women by a ratio of 1.5:1, and the incidence increases with age. Symptoms of GBS begin with a tingling or a pins and needles feeling in the toes and tips of fingers, which rapidly progresses to include the whole of the limbs. Weakness and numbness progress to a paralysis, which may involve respiratory muscles. Months can elapse before the patient s recovery begins. Substantial improvement occurs within the next 3-12 months in the majority of cases, but 20% of GBS patients are left with a residual disability and about 5% of patients die. In most cases of GBS, a link with C. jejuni infection is suspected.
The rapid test to detect C. jejuni strains that the research team of Dr. Anthony Moran and Dr. Martina Prendergast of the Department of Microbiology in NUI, Galway have developed, eliminates the need to grow large quantities of organism and substantially reduces the time needed for strain characterisation. "Hundreds of strains can be screened quickly and cheaply, and the test could be routinely used in hospital laboratories to detect potential disease-causing strains", says Dr. Moran. The research team is also investigating safety issues in the development of a C. jejuni vaccine. The work is funded as part of a three-year on-going project by the Irish Health Research Board.
Dr. Anthony Moran is available for interview on the details of his research.
Information from: Máire Mhic Uidhir, Press Officer. Tel. 091 750418